/*
* linux/drivers/char/serial.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
*
* Extensively rewritten by Theodore Ts'o, 8/16/92 -- 9/14/92. Now
* much more extensible to support other serial cards based on the
* 16450/16550A UART's. Added support for the AST FourPort and the
* Accent Async board.
*
* set_serial_info fixed to set the flags, custom divisor, and uart
* type fields. Fix suggested by Michael K. Johnson 12/12/92.
*
* TIOCMIWAIT, TIOCGICOUNT by Angelo Haritsis <ah@doc.ic.ac.uk>
*
* This module exports the following rs232 io functions:
*
* int rs_init(void);
* int rs_open(struct tty_struct * tty, struct file * filp)
*/
#include <linux/errno.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/timer.h>
#include <linux/interrupt.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/serial.h>
#include <linux/serial_reg.h>
#include <linux/config.h>
#include <linux/major.h>
#include <linux/string.h>
#include <linux/fcntl.h>
#include <linux/ptrace.h>
#include <linux/ioport.h>
#include <linux/mm.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/segment.h>
#include <asm/bitops.h>
DECLARE_TASK_QUEUE(tq_serial);
struct tty_driver serial_driver, callout_driver;
static int serial_refcount;
/* serial subtype definitions */
#define SERIAL_TYPE_NORMAL 1
#define SERIAL_TYPE_CALLOUT 2
/* number of characters left in xmit buffer before we ask for more */
#define WAKEUP_CHARS 256
/*
* Serial driver configuration section. Here are the various options:
*
* CONFIG_HUB6
* Enables support for the venerable Bell Technologies
* HUB6 card.
*
* SERIAL_PARANOIA_CHECK
* Check the magic number for the async_structure where
* ever possible.
*/
#define SERIAL_PARANOIA_CHECK
#define CONFIG_SERIAL_NOPAUSE_IO
#define SERIAL_DO_RESTART
#undef SERIAL_DEBUG_INTR
#undef SERIAL_DEBUG_OPEN
#undef SERIAL_DEBUG_FLOW
#define RS_STROBE_TIME (10*HZ)
#define RS_ISR_PASS_LIMIT 256
#define _INLINE_ inline
/*
* IRQ_timeout - How long the timeout should be for each IRQ
* should be after the IRQ has been active.
*/
static struct async_struct *IRQ_ports[16];
static struct rs_multiport_struct rs_multiport[16];
static int IRQ_timeout[16];
static volatile int rs_irq_triggered;
static volatile int rs_triggered;
static int rs_wild_int_mask;
static void autoconfig(struct async_struct * info);
static void change_speed(struct async_struct *info);
/*
* This assumes you have a 1.8432 MHz clock for your UART.
*
* It'd be nice if someone built a serial card with a 24.576 MHz
* clock, since the 16550A is capable of handling a top speed of 1.5
* megabits/second; but this requires the faster clock.
*/
#define BASE_BAUD ( 1843200 / 16 )
/* Standard COM flags (except for COM4, because of the 8514 problem) */
#define STD_COM_FLAGS (ASYNC_BOOT_AUTOCONF | ASYNC_SKIP_TEST )
#define STD_COM4_FLAGS ASYNC_BOOT_AUTOCONF
#define FOURPORT_FLAGS ASYNC_FOURPORT
#define ACCENT_FLAGS 0
#define BOCA_FLAGS 0
#define HUB6_FLAGS 0
/*
* The following define the access methods for the HUB6 card. All
* access is through two ports for all 24 possible chips. The card is
* selected through the high 2 bits, the port on that card with the
* "middle" 3 bits, and the register on that port with the bottom
* 3 bits.
*
* While the access port and interrupt is configurable, the default
* port locations are 0x302 for the port control register, and 0x303
* for the data read/write register. Normally, the interrupt is at irq3
* but can be anything from 3 to 7 inclusive. Note that using 3 will
* require disabling com2.
*/
#define C_P(card,port) (((card)<<6|(port)<<3) + 1)
struct async_struct rs_table[] = {
/* UART CLK PORT IRQ FLAGS */
{ 0, BASE_BAUD, 0x3F8, 4, STD_COM_FLAGS }, /* ttyS0 */
{ 0, BASE_BAUD, 0x2F8, 3, STD_COM_FLAGS }, /* ttyS1 */
{ 0, BASE_BAUD, 0x3E8, 4, STD_COM_FLAGS }, /* ttyS2 */
{ 0, BASE_BAUD, 0x2E8, 3, STD_COM4_FLAGS }, /* ttyS3 */
{ 0, BASE_BAUD, 0x1A0, 9, FOURPORT_FLAGS }, /* ttyS4 */
{ 0, BASE_BAUD, 0x1A8, 9, FOURPORT_FLAGS }, /* ttyS5 */
{ 0, BASE_BAUD, 0x1B0, 9, FOURPORT_FLAGS }, /* ttyS6 */
{ 0, BASE_BAUD, 0x1B8, 9, FOURPORT_FLAGS }, /* ttyS7 */
{ 0, BASE_BAUD, 0x2A0, 5, FOURPORT_FLAGS }, /* ttyS8 */
{ 0, BASE_BAUD, 0x2A8, 5, FOURPORT_FLAGS }, /* ttyS9 */
{ 0, BASE_BAUD, 0x2B0, 5, FOURPORT_FLAGS }, /* ttyS10 */
{ 0, BASE_BAUD, 0x2B8, 5, FOURPORT_FLAGS }, /* ttyS11 */
{ 0, BASE_BAUD, 0x330, 4, ACCENT_FLAGS }, /* ttyS12 */
{ 0, BASE_BAUD, 0x338, 4, ACCENT_FLAGS }, /* ttyS13 */
{ 0, BASE_BAUD, 0x000, 0, 0 }, /* ttyS14 (spare; user configurable) */
{ 0, BASE_BAUD, 0x000, 0, 0 }, /* ttyS15 (spare; user configurable) */
{ 0, BASE_BAUD, 0x100, 12, BOCA_FLAGS }, /* ttyS16 */
{ 0, BASE_BAUD, 0x108, 12, BOCA_FLAGS }, /* ttyS17 */
{ 0, BASE_BAUD, 0x110, 12, BOCA_FLAGS }, /* ttyS18 */
{ 0, BASE_BAUD, 0x118, 12, BOCA_FLAGS }, /* ttyS19 */
{ 0, BASE_BAUD, 0x120, 12, BOCA_FLAGS }, /* ttyS20 */
{ 0, BASE_BAUD, 0x128, 12, BOCA_FLAGS }, /* ttyS21 */
{ 0, BASE_BAUD, 0x130, 12, BOCA_FLAGS }, /* ttyS22 */
{ 0, BASE_BAUD, 0x138, 12, BOCA_FLAGS }, /* ttyS23 */
{ 0, BASE_BAUD, 0x140, 12, BOCA_FLAGS }, /* ttyS24 */
{ 0, BASE_BAUD, 0x148, 12, BOCA_FLAGS }, /* ttyS25 */
{ 0, BASE_BAUD, 0x150, 12, BOCA_FLAGS }, /* ttyS26 */
{ 0, BASE_BAUD, 0x158, 12, BOCA_FLAGS }, /* ttyS27 */
{ 0, BASE_BAUD, 0x160, 12, BOCA_FLAGS }, /* ttyS28 */
{ 0, BASE_BAUD, 0x168, 12, BOCA_FLAGS }, /* ttyS29 */
{ 0, BASE_BAUD, 0x170, 12, BOCA_FLAGS }, /* ttyS30 */
{ 0, BASE_BAUD, 0x178, 12, BOCA_FLAGS }, /* ttyS31 */
/* You can have up to four HUB6's in the system, but I've only
* included two cards here for a total of twelve ports.
*/
{ 0, BASE_BAUD, 0x302, 3, HUB6_FLAGS, C_P(0,0) }, /* ttyS32 */
{ 0, BASE_BAUD, 0x302, 3, HUB6_FLAGS, C_P(0,1) }, /* ttyS33 */
{ 0, BASE_BAUD, 0x302, 3, HUB6_FLAGS, C_P(0,2) }, /* ttyS34 */
{ 0, BASE_BAUD, 0x302, 3, HUB6_FLAGS, C_P(0,3) }, /* ttyS35 */
{ 0, BASE_BAUD, 0x302, 3, HUB6_FLAGS, C_P(0,4) }, /* ttyS36 */
{ 0, BASE_BAUD, 0x302, 3, HUB6_FLAGS, C_P(0,5) }, /* ttyS37 */
{ 0, BASE_BAUD, 0x302, 3, HUB6_FLAGS, C_P(1,0) }, /* ttyS32 */
{ 0, BASE_BAUD, 0x302, 3, HUB6_FLAGS, C_P(1,1) }, /* ttyS33 */
{ 0, BASE_BAUD, 0x302, 3, HUB6_FLAGS, C_P(1,2) }, /* ttyS34 */
{ 0, BASE_BAUD, 0x302, 3, HUB6_FLAGS, C_P(1,3) }, /* ttyS35 */
{ 0, BASE_BAUD, 0x302, 3, HUB6_FLAGS, C_P(1,4) }, /* ttyS36 */
{ 0, BASE_BAUD, 0x302, 3, HUB6_FLAGS, C_P(1,5) }, /* ttyS37 */
};
#define NR_PORTS (sizeof(rs_table)/sizeof(struct async_struct))
static struct tty_struct *serial_table[NR_PORTS];
static struct termios *serial_termios[NR_PORTS];
static struct termios *serial_termios_locked[NR_PORTS];
#ifndef MIN
#define MIN(a,b) ((a) < (b) ? (a) : (b))
#endif
/*
* tmp_buf is used as a temporary buffer by serial_write. We need to
* lock it in case the memcpy_fromfs blocks while swapping in a page,
* and some other program tries to do a serial write at the same time.
* Since the lock will only come under contention when the system is
* swapping and available memory is low, it makes sense to share one
* buffer across all the serial ports, since it significantly saves
* memory if large numbers of serial ports are open.
*/
static unsigned char *tmp_buf = 0;
static struct semaphore tmp_buf_sem = MUTEX;
static inline int serial_paranoia_check(struct async_struct *info,
kdev_t device, const char *routine)
{
#ifdef SERIAL_PARANOIA_CHECK
static const char *badmagic =
"Warning: bad magic number for serial struct (%s) in %s\n";
static const char *badinfo =
"Warning: null async_struct for (%s) in %s\n";
if (!info) {
printk(badinfo, kdevname(device), routine);
return 1;
}
if (info->magic != SERIAL_MAGIC) {
printk(badmagic, kdevname(device), routine);
return 1;
}
#endif
return 0;
}
/*
* This is used to figure out the divisor speeds and the timeouts
*/
static int baud_table[] = {
0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800,
9600, 19200, 38400, 57600, 115200, 0 };
static inline unsigned int serial_in(struct async_struct *info, int offset)
{
#ifdef CONFIG_HUB6
if (info->hub6) {
outb(info->hub6 - 1 + offset, info->port);
return inb(info->port+1);
} else
#endif
return inb(info->port + offset);
}
static inline unsigned int serial_inp(struct async_struct *info, int offset)
{
#ifdef CONFIG_HUB6
if (info->hub6) {
outb(info->hub6 - 1 + offset, info->port);
return inb_p(info->port+1);
} else
#endif
#ifdef CONFIG_SERIAL_NOPAUSE_IO
return inb(info->port + offset);
#else
return inb_p(info->port + offset);
#endif
}
static inline void serial_out(struct async_struct *info, int offset, int value)
{
#ifdef CONFIG_HUB6
if (info->hub6) {
outb(info->hub6 - 1 + offset, info->port);
outb(value, info->port+1);
} else
#endif
outb(value, info->port+offset);
}
static inline void serial_outp(struct async_struct *info, int offset,
int value)
{
#ifdef CONFIG_HUB6
if (info->hub6) {
outb(info->hub6 - 1 + offset, info->port);
outb_p(value, info->port+1);
} else
#endif
#ifdef CONFIG_SERIAL_NOPAUSE_IO
outb(value, info->port+offset);
#else
outb_p(value, info->port+offset);
#endif
}
/*
* ------------------------------------------------------------
* rs_stop() and rs_start()
*
* This routines are called before setting or resetting tty->stopped.
* They enable or disable transmitter interrupts, as necessary.
* ------------------------------------------------------------
*/
static void rs_stop(struct tty_struct *tty)
{
struct async_struct *info = (struct async_struct *)tty->driver_data;
unsigned long flags;
if (serial_paranoia_check(info, tty->device, "rs_stop"))
return;
save_flags(flags); cli();
if (info->IER & UART_IER_THRI) {
info->IER &= ~UART_IER_THRI;
serial_out(info, UART_IER, info->IER);
}
restore_flags(flags);
}
static void rs_start(struct tty_struct *tty)
{
struct async_struct *info = (struct async_struct *)tty->driver_data;
unsigned long flags;
if (serial_paranoia_check(info, tty->device, "rs_start"))
return;
save_flags(flags); cli();
if (info->xmit_cnt && info->xmit_buf && !(info->IER & UART_IER_THRI)) {
info->IER |= UART_IER_THRI;
serial_out(info, UART_IER, info->IER);
}
restore_flags(flags);
}
/*
* ----------------------------------------------------------------------
*
* Here starts the interrupt handling routines. All of the following
* subroutines are declared as inline and are folded into
* rs_interrupt(). They were separated out for readability's sake.
*
* Note: rs_interrupt() is a "fast" interrupt, which means that it
* runs with interrupts turned off. People who may want to modify
* rs_interrupt() should try to keep the interrupt handler as fast as
* possible. After you are done making modifications, it is not a bad
* idea to do:
*
* gcc -S -DKERNEL -Wall -Wstrict-prototypes -O6 -fomit-frame-pointer serial.c
*
* and look at the resulting assemble code in serial.s.
*
* - Ted Ts'o (tytso@mit.edu), 7-Mar-93
* -----------------------------------------------------------------------
*/
/*
* This is the serial driver's interrupt routine while we are probing
* for submarines.
*/
static void rs_probe(int irq, struct pt_regs * regs)
{
rs_irq_triggered = irq;
rs_triggered |= 1 << irq;
return;
}
/*
* This routine is used by the interrupt handler to schedule
* processing in the software interrupt portion of the driver.
*/
static _INLINE_ void rs_sched_event(struct async_struct *info,
int event)
{
info->event |= 1 << event;
queue_task_irq_off(&info->tqueue, &tq_serial);
mark_bh(SERIAL_BH);
}
static _INLINE_ void receive_chars(struct async_struct *info,
int *status)
{
struct tty_struct *tty = info->tty;
unsigned char ch;
int ignored = 0;
do {
ch = serial_inp(info, UART_RX);
if (*status & info->ignore_status_mask) {
if (++ignored > 100)
break;
goto ignore_char;
}
if (tty->flip.count >= TTY_FLIPBUF_SIZE)
break;
tty->flip.count++;
if (*status & (UART_LSR_BI)) {
printk("handling break....");
*tty->flip.flag_buf_ptr++ = TTY_BREAK;
if (info->flags & ASYNC_SAK)
do_SAK(tty);
} else if (*status & UART_LSR_PE)
*tty->flip.flag_buf_ptr++ = TTY_PARITY;
else if (*status & UART_LSR_FE)
*tty->flip.flag_buf_ptr++ = TTY_FRAME;
else if (*status & UART_LSR_OE)
*tty->flip.flag_buf_ptr++ = TTY_OVERRUN;
else
*tty->flip.flag_buf_ptr++ = 0;
*tty->flip.char_buf_ptr++ = ch;
ignore_char:
*status = serial_inp(info, UART_LSR) & info->read_status_mask;
} while (*status & UART_LSR_DR);
queue_task_irq_off(&tty->flip.tqueue, &tq_timer);
#ifdef SERIAL_DEBUG_INTR
printk("DR...");
#endif
}
static _INLINE_ void transmit_chars(struct async_struct *info, int *intr_done)
{
int count;
if (info->x_char) {
serial_outp(info, UART_TX, info->x_char);
info->x_char = 0;
if (intr_done)
*intr_done = 0;
return;
}
if ((info->xmit_cnt <= 0) || info->tty->stopped ||
info->tty->hw_stopped) {
info->IER &= ~UART_IER_THRI;
serial_out(info, UART_IER, info->IER);
return;
}
count = info->xmit_fifo_size;
do {
serial_out(info, UART_TX, info->xmit_buf[info->xmit_tail++]);
info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
if (--info->xmit_cnt <= 0)
break;
} while (--count > 0);
if (info->xmit_cnt < WAKEUP_CHARS)
rs_sched_event(info, RS_EVENT_WRITE_WAKEUP);
#ifdef SERIAL_DEBUG_INTR
printk("THRE...");
#endif
if (intr_done)
*intr_done = 0;
if (info->xmit_cnt <= 0) {
info->IER &= ~UART_IER_THRI;
serial_out(info, UART_IER, info->IER);
}
}
static _INLINE_ void check_modem_status(struct async_struct *info)
{
int status;
status = serial_in(info, UART_MSR);
if (status & UART_MSR_ANY_DELTA) {
/* update input line counters */
if (status & UART_MSR_TERI)
info->icount.rng++;
if (status & UART_MSR_DDSR)
info->icount.dsr++;
if (status & UART_MSR_DDCD)
info->icount.dcd++;
if (status & UART_MSR_DCTS)
info->icount.cts++;
wake_up_interruptible(&info->delta_msr_wait);
}
if ((info->flags & ASYNC_CHECK_CD) && (status & UART_MSR_DDCD)) {
#if (defined(SERIAL_DEBUG_OPEN) || defined(SERIAL_DEBUG_INTR))
printk("ttys%d CD now %s...", info->line,
(status & UART_MSR_DCD) ? "on" : "off");
#endif
if (status & UART_MSR_DCD)
wake_up_interruptible(&info->open_wait);
else if (!((info->flags & ASYNC_CALLOUT_ACTIVE) &&
(info->flags & ASYNC_CALLOUT_NOHUP))) {
#ifdef SERIAL_DEBUG_OPEN
printk("scheduling hangup...");
#endif
queue_task_irq_off(&info->tqueue_hangup,
&tq_scheduler);
}
}
if (info->flags & ASYNC_CTS_FLOW) {
if (info->tty->hw_stopped) {
if (status & UART_MSR_CTS) {
#if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW))
printk("CTS tx start...");
#endif
info->tty->hw_stopped = 0;
info->IER |= UART_IER_THRI;
serial_out(info, UART_IER, info->IER);
rs_sched_event(info, RS_EVENT_WRITE_WAKEUP);
return;
}
} else {
if (!(status & UART_MSR_CTS)) {
#if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW))
printk("CTS tx stop...");
#endif
info->tty->hw_stopped = 1;
info->IER &= ~UART_IER_THRI;
serial_out(info, UART_IER, info->IER);
}
}
}
}
/*
* This is the serial driver's generic interrupt routine
*/
static void rs_interrupt(int irq, struct pt_regs * regs)
{
int status;
struct async_struct * info;
int pass_counter = 0;
struct async_struct *end_mark = 0;
int first_multi = 0;
struct rs_multiport_struct *multi;
#ifdef SERIAL_DEBUG_INTR
printk("rs_interrupt(%d)...", irq);
#endif
info = IRQ_ports[irq];
if (!info)
return;
multi = &rs_multiport[irq];
if (multi->port_monitor)
first_multi = inb(multi->port_monitor);
do {
if (!info->tty ||
(serial_in(info, UART_IIR) & UART_IIR_NO_INT)) {
if (!end_mark)
end_mark = info;
goto next;
}
end_mark = 0;
info->last_active = jiffies;
status = serial_inp(info, UART_LSR) & info->read_status_mask;
#ifdef SERIAL_DEBUG_INTR
printk("status = %x...", status);
#endif
if (status & UART_LSR_DR)
receive_chars(info, &status);
check_modem_status(info);
if (status & UART_LSR_THRE)
transmit_chars(info, 0);
next:
info = info->next_port;
if (!info) {
info = IRQ_ports[irq];
if (pass_counter++ > RS_ISR_PASS_LIMIT) {
#if 0
printk("rs loop break\n");
#endif
break; /* Prevent infinite loops */
}
continue;
}
} while (end_mark != info);
if (multi->port_monitor)
printk("rs port monitor (normal) irq %d: 0x%x, 0x%x\n",
info->irq, first_multi, inb(multi->port_monitor));
#ifdef SERIAL_DEBUG_INTR
printk("end.\n");
#endif
}
/*
* This is the serial driver's interrupt routine for a single port
*/
static void rs_interrupt_single(int irq, struct pt_regs * regs)
{
int status;
int pass_counter = 0;
int first_multi = 0;
struct async_struct * info;
struct rs_multiport_struct *multi;
#ifdef SERIAL_DEBUG_INTR
printk("rs_interrupt_single(%d)...", irq);
#endif
info = IRQ_ports[irq];
if (!info || !info->tty)
return;
multi = &rs_multiport[irq];
if (multi->port_monitor)
first_multi = inb(multi->port_monitor);
do {
status = serial_inp(info, UART_LSR) & info->read_status_mask;
#ifdef SERIAL_DEBUG_INTR
printk("status = %x...", status);
#endif
if (status & UART_LSR_DR)
receive_chars(info, &status);
check_modem_status(info);
if (status & UART_LSR_THRE)
transmit_chars(info, 0);
if (pass_counter++ > RS_ISR_PASS_LIMIT) {
#if 0
printk("rs_single loop break.\n");
#endif
break;
}
} while (!(serial_in(info, UART_IIR) & UART_IIR_NO_INT));
info->last_active = jiffies;
if (multi->port_monitor)
printk("rs port monitor (single) irq %d: 0x%x, 0x%x\n",
info->irq, first_multi, inb(multi->port_monitor));
#ifdef SERIAL_DEBUG_INTR
printk("end.\n");
#endif
}
/*
* This is the serial driver's for multiport boards
*/
static void rs_interrupt_multi(int irq, struct pt_regs * regs)
{
int status;
struct async_struct * info;
int pass_counter = 0;
int first_multi= 0;
struct rs_multiport_struct *multi;
#ifdef SERIAL_DEBUG_INTR
printk("rs_interrupt_multi(%d)...", irq);
#endif
info = IRQ_ports[irq];
if (!info)
return;
multi = &rs_multiport[irq];
if (!multi->port1) {
/* Should never happen */
printk("rs_interrupt_multi: NULL port1!\n");
return;
}
if (multi->port_monitor)
first_multi = inb(multi->port_monitor);
while (1) {
if (!info->tty ||
(serial_in(info, UART_IIR) & UART_IIR_NO_INT))
goto next;
info->last_active = jiffies;
status = serial_inp(info, UART_LSR) & info->read_status_mask;
#ifdef SERIAL_DEBUG_INTR
printk("status = %x...", status);
#endif
if (status & UART_LSR_DR)
receive_chars(info, &status);
check_modem_status(info);
if (status & UART_LSR_THRE)
transmit_chars(info, 0);
next:
info = info->next_port;
if (info)
continue;
info = IRQ_ports[irq];
if (pass_counter++ > RS_ISR_PASS_LIMIT) {
#if 1
printk("rs_multi loop break\n");
#endif
break; /* Prevent infinite loops */
}
if (multi->port_monitor)
printk("rs port monitor irq %d: 0x%x, 0x%x\n",
info->irq, first_multi,
inb(multi->port_monitor));
if ((inb(multi->port1) & multi->mask1) != multi->match1)
continue;
if (!multi->port2)
break;
if ((inb(multi->port2) & multi->mask2) != multi->match2)
continue;
if (!multi->port3)
break;
if ((inb(multi->port3) & multi->mask3) != multi->match3)
continue;
if (!multi->port4)
break;
if ((inb(multi->port4) & multi->mask4) == multi->match4)
continue;
break;
}
#ifdef SERIAL_DEBUG_INTR
printk("end.\n");
#endif
}
/*
* -------------------------------------------------------------------
* Here ends the serial interrupt routines.
* -------------------------------------------------------------------
*/
/*
* This routine is used to handle the "bottom half" processing for the
* serial driver, known also the "software interrupt" processing.
* This processing is done at the kernel interrupt level, after the
* rs_interrupt() has returned, BUT WITH INTERRUPTS TURNED ON. This
* is where time-consuming activities which can not be done in the
* interrupt driver proper are done; the interrupt driver schedules
* them using rs_sched_event(), and they get done here.
*/
static void do_serial_bh(void *unused)
{
run_task_queue(&tq_serial);
}
static void do_softint(void *private_)
{
struct async_struct *info = (struct async_struct *) private_;
struct tty_struct *tty;
tty = info->tty;
if (!tty)
return;
if (clear_bit(RS_EVENT_WRITE_WAKEUP, &info->event)) {
if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
tty->ldisc.write_wakeup)
(tty->ldisc.write_wakeup)(tty);
wake_up_interruptible(&tty->write_wait);
}
}
/*
* This routine is called from the scheduler tqueue when the interrupt
* routine has signalled that a hangup has occurred. The path of
* hangup processing is:
*
* serial interrupt routine -> (scheduler tqueue) ->
* do_serial_hangup() -> tty->hangup() -> rs_hangup()
*
*/
static void do_serial_hangup(void *private_)
{
struct async_struct *info = (struct async_struct *) private_;
struct tty_struct *tty;
tty = info->tty;
if (!tty)
return;
tty_hangup(tty);
}
/*
* This subroutine is called when the RS_TIMER goes off. It is used
* by the serial driver to handle ports that do not have an interrupt
* (irq=0). This doesn't work very well for 16450's, but gives barely
* passable results for a 16550A. (Although at the expense of much
* CPU overhead).
*/
static void rs_timer(void)
{
static unsigned long last_strobe = 0;
struct async_struct *info;
unsigned int i;
if ((jiffies - last_strobe) >= RS_STROBE_TIME) {
for (i=1; i < 16; i++) {
info = IRQ_ports[i];
if (!info)
continue;
cli();
if (info->next_port) {
do {
serial_out(info, UART_IER, 0);
info->IER |= UART_IER_THRI;
serial_out(info, UART_IER, info->IER);
info = info->next_port;
} while (info);
if (rs_multiport[i].port1)
rs_interrupt_multi(i, NULL);
else
rs_interrupt(i, NULL);
} else
rs_interrupt_single(i, NULL);
sti();
}
}
last_strobe = jiffies;
timer_table[RS_TIMER].expires = jiffies + RS_STROBE_TIME;
timer_active |= 1 << RS_TIMER;
if (IRQ_ports[0]) {
cli();
rs_interrupt(0, NULL);
sti();
timer_table[RS_TIMER].expires = jiffies + IRQ_timeout[0] - 2;
}
}
/*
* ---------------------------------------------------------------
* Low level utility subroutines for the serial driver: routines to
* figure out the appropriate timeout for an interrupt chain, routines
* to initialize and startup a serial port, and routines to shutdown a
* serial port. Useful stuff like that.
* ---------------------------------------------------------------
*/
/*
* Grab all interrupts in preparation for doing an automatic irq
* detection. dontgrab is a mask of irq's _not_ to grab. Returns a
* mask of irq's which were grabbed and should therefore be freed
* using free_all_interrupts().
*/
static int grab_all_interrupts(int dontgrab)
{
int irq_lines = 0;
int i, mask;
for (i = 0, mask = 1; i < 16; i++, mask <<= 1) {
if (!(mask & dontgrab) && !request_irq(i, rs_probe, SA_INTERRUPT, "serial probe")) {
irq_lines |= mask;
}
}
return irq_lines;
}
/*
* Release all interrupts grabbed by grab_all_interrupts
*/
static void free_all_interrupts(int irq_lines)
{
int i;
for (i = 0; i < 16; i++) {
if (irq_lines & (1 << i))
free_irq(i);
}
}
/*
* This routine figures out the correct timeout for a particular IRQ.
* It uses the smallest timeout of all of the serial ports in a
* particular interrupt chain. Now only used for IRQ 0....
*/
static void figure_IRQ_timeout(int irq)
{
struct async_struct *info;
int timeout = 60*HZ; /* 60 seconds === a long time :-) */
info = IRQ_ports[irq];
if (!info) {
IRQ_timeout[irq] = 60*HZ;
return;
}
while (info) {
if (info->timeout < timeout)
timeout = info->timeout;
info = info->next_port;
}
if (!irq)
timeout = timeout / 2;
IRQ_timeout[irq] = timeout ? timeout : 1;
}
static int startup(struct async_struct * info)
{
unsigned short ICP;
unsigned long flags;
int retval;
void (*handler)(int, struct pt_regs *);
unsigned long page;
page = get_free_page(GFP_KERNEL);
if (!page)
return -ENOMEM;
save_flags(flags); cli();
if (info->flags & ASYNC_INITIALIZED) {
free_page(page);
restore_flags(flags);
return 0;
}
if (!info->port || !info->type) {
if (info->tty)
set_bit(TTY_IO_ERROR, &info->tty->flags);
free_page(page);
restore_flags(flags);
return 0;
}
if (info->xmit_buf)
free_page(page);
else
info->xmit_buf = (unsigned char *) page;
#ifdef SERIAL_DEBUG_OPEN
printk("starting up ttys%d (irq %d)...", info->line, info->irq);
#endif
/*
* Clear the FIFO buffers and disable them
* (they will be reenabled in change_speed())
*/
if (info->type == PORT_16650) {
serial_outp(info, UART_FCR, (UART_FCR_CLEAR_RCVR |
UART_FCR_CLEAR_XMIT));
info->xmit_fifo_size = 1; /* disabled for now */
} else if (info->type == PORT_16550A) {
serial_outp(info, UART_FCR, (UART_FCR_CLEAR_RCVR |
UART_FCR_CLEAR_XMIT));
info->xmit_fifo_size = 16;
} else
info->xmit_fifo_size = 1;
/*
* At this point there's no way the LSR could still be 0xFF;
* if it is, then bail out, because there's likely no UART
* here.
*/
if (serial_inp(info, UART_LSR) == 0xff) {
restore_flags(flags);
if (suser()) {
if (info->tty)
set_bit(TTY_IO_ERROR, &info->tty->flags);
return 0;
} else
return -ENODEV;
}
/*
* Allocate the IRQ if necessary
*/
if (info->irq && (!IRQ_ports[info->irq] ||
!IRQ_ports[info->irq]->next_port)) {
if (IRQ_ports[info->irq]) {
free_irq(info->irq);
if (rs_multiport[info->irq].port1)
handler = rs_interrupt_multi;
else
handler = rs_interrupt;
} else
handler = rs_interrupt_single;
retval = request_irq(info->irq, handler, SA_INTERRUPT, "serial");
if (retval) {
restore_flags(flags);
if (suser()) {
if (info->tty)
set_bit(TTY_IO_ERROR,
&info->tty->flags);
return 0;
} else
return retval;
}
}
/*
* Clear the interrupt registers.
*/
/* (void) serial_inp(info, UART_LSR); */ /* (see above) */
(void) serial_inp(info, UART_RX);
(void) serial_inp(info, UART_IIR);
(void) serial_inp(info, UART_MSR);
/*
* Now, initialize the UART
*/
serial_outp(info, UART_LCR, UART_LCR_WLEN8); /* reset DLAB */
if (info->flags & ASYNC_FOURPORT) {
info->MCR = UART_MCR_DTR | UART_MCR_RTS;
info->MCR_noint = UART_MCR_DTR | UART_MCR_OUT1;
} else {
info->MCR = UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2;
info->MCR_noint = UART_MCR_DTR | UART_MCR_RTS;
}
#if defined(__alpha__) && !defined(CONFIG_PCI)
info->MCR |= UART_MCR_OUT1 | UART_MCR_OUT2;
info->MCR_noint |= UART_MCR_OUT1 | UART_MCR_OUT2;
#endif
if (info->irq == 0)
info->MCR = info->MCR_noint;
serial_outp(info, UART_MCR, info->MCR);
/*
* Finally, enable interrupts
*/
info->IER = UART_IER_MSI | UART_IER_RLSI | UART_IER_RDI;
serial_outp(info, UART_IER, info->IER); /* enable interrupts */
if (info->flags & ASYNC_FOURPORT) {
/* Enable interrupts on the AST Fourport board */
ICP = (info->port & 0xFE0) | 0x01F;
outb_p(0x80, ICP);
(void) inb_p(ICP);
}
/*
* And clear the interrupt registers again for luck.
*/
(void)serial_inp(info, UART_LSR);
(void)serial_inp(info, UART_RX);
(void)serial_inp(info, UART_IIR);
(void)serial_inp(info, UART_MSR);
if (info->tty)
clear_bit(TTY_IO_ERROR, &info->tty->flags);
info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
/*
* Insert serial port into IRQ chain.
*/
info->prev_port = 0;
info->next_port = IRQ_ports[info->irq];
if (info->next_port)
info->next_port->prev_port = info;
IRQ_ports[info->irq] = info;
figure_IRQ_timeout(info->irq);
/*
* Set up serial timers...
*/
timer_table[RS_TIMER].expires = jiffies + 2*HZ/100;
timer_active |= 1 << RS_TIMER;
/*
* and set the speed of the serial port
*/
change_speed(info);
info->flags |= ASYNC_INITIALIZED;
restore_flags(flags);
return 0;
}
/*
* This routine will shutdown a serial port; interrupts are disabled, and
* DTR is dropped if the hangup on close termio flag is on.
*/
static void shutdown(struct async_struct * info)
{
unsigned long flags;
int retval;
if (!(info->flags & ASYNC_INITIALIZED))
return;
#ifdef SERIAL_DEBUG_OPEN
printk("Shutting down serial port %d (irq %d)....", info->line,
info->irq);
#endif
save_flags(flags); cli(); /* Disable interrupts */
/*
* First unlink the serial port from the IRQ chain...
*/
if (info->next_port)
info->next_port->prev_port = info->prev_port;
if (info->prev_port)
info->prev_port->next_port = info->next_port;
else
IRQ_ports[info->irq] = info->next_port;
figure_IRQ_timeout(info->irq);
/*
* Free the IRQ, if necessary
*/
if (info->irq && (!IRQ_ports[info->irq] ||
!IRQ_ports[info->irq]->next_port)) {
if (IRQ_ports[info->irq]) {
free_irq(info->irq);
retval = request_irq(info->irq, rs_interrupt_single, SA_INTERRUPT, "serial");
if (retval)
printk("serial shutdown: request_irq: error %d"
" Couldn't reacquire IRQ.\n", retval);
} else
free_irq(info->irq);
}
if (info->xmit_buf) {
free_page((unsigned long) info->xmit_buf);
info->xmit_buf = 0;
}
info->IER = 0;
serial_outp(info, UART_IER, 0x00); /* disable all intrs */
if (info->flags & ASYNC_FOURPORT) {
/* reset interrupts on the AST Fourport board */
(void) inb((info->port & 0xFE0) | 0x01F);
}
if (!info->tty || (info->tty->termios->c_cflag & HUPCL)) {
info->MCR &= ~(UART_MCR_DTR|UART_MCR_RTS);
info->MCR_noint &= ~(UART_MCR_DTR|UART_MCR_RTS);
}
serial_outp(info, UART_MCR, info->MCR_noint);
/* disable FIFO's */
serial_outp(info, UART_FCR, (UART_FCR_CLEAR_RCVR |
UART_FCR_CLEAR_XMIT));
(void)serial_in(info, UART_RX); /* read data port to reset things */
if (info->tty)
set_bit(TTY_IO_ERROR, &info->tty->flags);
info->flags &= ~ASYNC_INITIALIZED;
restore_flags(flags);
}
/*
* This routine is called to set the UART divisor registers to match
* the specified baud rate for a serial port.
*/
static void change_speed(struct async_struct *info)
{
unsigned short port;
int quot = 0;
unsigned cflag,cval,fcr;
int i;
if (!info->tty || !info->tty->termios)
return;
cflag = info->tty->termios->c_cflag;
if (!(port = info->port))
return;
i = cflag & CBAUD;
if (i & CBAUDEX) {
i &= ~CBAUDEX;
if (i < 1 || i > 2)
info->tty->termios->c_cflag &= ~CBAUDEX;
else
i += 15;
}
if (i == 15) {
if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
i += 1;
if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
i += 2;
if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST)
quot = info->custom_divisor;
}
if (quot) {
info->timeout = ((info->xmit_fifo_size*HZ*15*quot) /
info->baud_base) + 2;
} else if (baud_table[i] == 134) {
quot = (2*info->baud_base / 269);
info->timeout = (info->xmit_fifo_size*HZ*30/269) + 2;
} else if (baud_table[i]) {
quot = info->baud_base / baud_table[i];
info->timeout = (info->xmit_fifo_size*HZ*15/baud_table[i]) + 2;
} else {
quot = 0;
info->timeout = 0;
}
if (quot) {
info->MCR |= UART_MCR_DTR;
info->MCR_noint |= UART_MCR_DTR;
cli();
serial_out(info, UART_MCR, info->MCR);
sti();
} else {
info->MCR &= ~UART_MCR_DTR;
info->MCR_noint &= ~UART_MCR_DTR;
cli();
serial_out(info, UART_MCR, info->MCR);
sti();
return;
}
/* byte size and parity */
switch (cflag & CSIZE) {
case CS5: cval = 0x00; break;
case CS6: cval = 0x01; break;
case CS7: cval = 0x02; break;
case CS8: cval = 0x03; break;
default: cval = 0x00; break; /* too keep GCC shut... */
}
if (cflag & CSTOPB) {
cval |= 0x04;
}
if (cflag & PARENB)
cval |= UART_LCR_PARITY;
if (!(cflag & PARODD))
cval |= UART_LCR_EPAR;
if (info->type == PORT_16550A) {
if ((info->baud_base / quot) < 2400)
fcr = UART_FCR_ENABLE_FIFO | UART_FCR_TRIGGER_1;
else
fcr = UART_FCR_ENABLE_FIFO | UART_FCR_TRIGGER_8;
} else if (info->type == PORT_16650) {
/*
* On the 16650, we disable the FIFOs altogether
* because of a design bug in how the implement
* things. We could support it by completely changing
* how we handle the interrupt driver, but not today....
*
* N.B. Because there's no way to set a FIFO trigger
* at 1 char, we'd probably disable at speed below
* 2400 baud anyway...
*/
fcr = 0;
} else
fcr = 0;
/* CTS flow control flag and modem status interrupts */
info->IER &= ~UART_IER_MSI;
if (cflag & CRTSCTS) {
info->flags |= ASYNC_CTS_FLOW;
info->IER |= UART_IER_MSI;
} else
info->flags &= ~ASYNC_CTS_FLOW;
if (cflag & CLOCAL)
info->flags &= ~ASYNC_CHECK_CD;
else {
info->flags |= ASYNC_CHECK_CD;
info->IER |= UART_IER_MSI;
}
serial_out(info, UART_IER, info->IER);
/*
* Set up parity check flag
*/
info->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
if (I_INPCK(info->tty))
info->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
if (I_BRKINT(info->tty) || I_PARMRK(info->tty))
info->read_status_mask |= UART_LSR_BI;
info->ignore_status_mask = 0;
if (I_IGNPAR(info->tty)) {
info->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
info->read_status_mask |= UART_LSR_PE | UART_LSR_FE;
}
if (I_IGNBRK(info->tty)) {
info->ignore_status_mask |= UART_LSR_BI;
info->read_status_mask |= UART_LSR_BI;
/*
* If we're ignore parity and break indicators, ignore
* overruns too. (For real raw support).
*/
if (I_IGNPAR(info->tty)) {
info->ignore_status_mask |= UART_LSR_OE;
info->read_status_mask |= UART_LSR_OE;
}
}
cli();
serial_outp(info, UART_LCR, cval | UART_LCR_DLAB); /* set DLAB */
serial_outp(info, UART_DLL, quot & 0xff); /* LS of divisor */
serial_outp(info, UART_DLM, quot >> 8); /* MS of divisor */
serial_outp(info, UART_LCR, cval); /* reset DLAB */
serial_outp(info, UART_FCR, fcr); /* set fcr */
sti();
}
static void rs_put_char(struct tty_struct *tty, unsigned char ch)
{
struct async_struct *info = (struct async_struct *)tty->driver_data;
unsigned long flags;
if (serial_paranoia_check(info, tty->device, "rs_put_char"))
return;
if (!tty || !info->xmit_buf)
return;
save_flags(flags); cli();
if (info->xmit_cnt >= SERIAL_XMIT_SIZE - 1) {
restore_flags(flags);
return;
}
info->xmit_buf[info->xmit_head++] = ch;
info->xmit_head &= SERIAL_XMIT_SIZE-1;
info->xmit_cnt++;
restore_flags(flags);
}
static void rs_flush_chars(struct tty_struct *tty)
{
struct async_struct *info = (struct async_struct *)tty->driver_data;
unsigned long flags;
if (serial_paranoia_check(info, tty->device, "rs_flush_chars"))
return;
if (info->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped ||
!info->xmit_buf)
return;
save_flags(flags); cli();
info->IER |= UART_IER_THRI;
serial_out(info, UART_IER, info->IER);
restore_flags(flags);
}
static int rs_write(struct tty_struct * tty, int from_user,
const unsigned char *buf, int count)
{
int c, total = 0;
struct async_struct *info = (struct async_struct *)tty->driver_data;
unsigned long flags;
if (serial_paranoia_check(info, tty->device, "rs_write"))
return 0;
if (!tty || !info->xmit_buf || !tmp_buf)
return 0;
if (from_user)
down(&tmp_buf_sem);
save_flags(flags);
while (1) {
cli();
c = MIN(count, MIN(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
SERIAL_XMIT_SIZE - info->xmit_head));
if (c <= 0)
break;
if (from_user) {
memcpy_fromfs(tmp_buf, buf, c);
c = MIN(c, MIN(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
SERIAL_XMIT_SIZE - info->xmit_head));
memcpy(info->xmit_buf + info->xmit_head, tmp_buf, c);
} else
memcpy(info->xmit_buf + info->xmit_head, buf, c);
info->xmit_head = (info->xmit_head + c) & (SERIAL_XMIT_SIZE-1);
info->xmit_cnt += c;
restore_flags(flags);
buf += c;
count -= c;
total += c;
}
if (from_user)
up(&tmp_buf_sem);
if (info->xmit_cnt && !tty->stopped && !tty->hw_stopped &&
!(info->IER & UART_IER_THRI)) {
info->IER |= UART_IER_THRI;
serial_out(info, UART_IER, info->IER);
}
restore_flags(flags);
return total;
}
static int rs_write_room(struct tty_struct *tty)
{
struct async_struct *info = (struct async_struct *)tty->driver_data;
int ret;
if (serial_paranoia_check(info, tty->device, "rs_write_room"))
return 0;
ret = SERIAL_XMIT_SIZE - info->xmit_cnt - 1;
if (ret < 0)
ret = 0;
return ret;
}
static int rs_chars_in_buffer(struct tty_struct *tty)
{
struct async_struct *info = (struct async_struct *)tty->driver_data;
if (serial_paranoia_check(info, tty->device, "rs_chars_in_buffer"))
return 0;
return info->xmit_cnt;
}
static void rs_flush_buffer(struct tty_struct *tty)
{
struct async_struct *info = (struct async_struct *)tty->driver_data;
if (serial_paranoia_check(info, tty->device, "rs_flush_buffer"))
return;
cli();
info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
sti();
wake_up_interruptible(&tty->write_wait);
if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
tty->ldisc.write_wakeup)
(tty->ldisc.write_wakeup)(tty);
}
/*
* ------------------------------------------------------------
* rs_throttle()
*
* This routine is called by the upper-layer tty layer to signal that
* incoming characters should be throttled.
* ------------------------------------------------------------
*/
static void rs_throttle(struct tty_struct * tty)
{
struct async_struct *info = (struct async_struct *)tty->driver_data;
#ifdef SERIAL_DEBUG_THROTTLE
char buf[64];
printk("throttle %s: %d....\n", _tty_name(tty, buf),
tty->ldisc.chars_in_buffer(tty));
#endif
if (serial_paranoia_check(info, tty->device, "rs_throttle"))
return;
if (I_IXOFF(tty))
info->x_char = STOP_CHAR(tty);
info->MCR &= ~UART_MCR_RTS;
info->MCR_noint &= ~UART_MCR_RTS;
cli();
serial_out(info, UART_MCR, info->MCR);
sti();
}
static void rs_unthrottle(struct tty_struct * tty)
{
struct async_struct *info = (struct async_struct *)tty->driver_data;
#ifdef SERIAL_DEBUG_THROTTLE
char buf[64];
printk("unthrottle %s: %d....\n", _tty_name(tty, buf),
tty->ldisc.chars_in_buffer(tty));
#endif
if (serial_paranoia_check(info, tty->device, "rs_unthrottle"))
return;
if (I_IXOFF(tty)) {
if (info->x_char)
info->x_char = 0;
else
info->x_char = START_CHAR(tty);
}
info->MCR |= UART_MCR_RTS;
info->MCR_noint |= UART_MCR_RTS;
cli();
serial_out(info, UART_MCR, info->MCR);
sti();
}
/*
* ------------------------------------------------------------
* rs_ioctl() and friends
* ------------------------------------------------------------
*/
static int get_serial_info(struct async_struct * info,
struct serial_struct * retinfo)
{
struct serial_struct tmp;
if (!retinfo)
return -EFAULT;
memset(&tmp, 0, sizeof(tmp));
tmp.type = info->type;
tmp.line = info->line;
tmp.port = info->port;
tmp.irq = info->irq;
tmp.flags = info->flags;
tmp.baud_base = info->baud_base;
tmp.close_delay = info->close_delay;
tmp.closing_wait = info->closing_wait;
tmp.custom_divisor = info->custom_divisor;
tmp.hub6 = info->hub6;
memcpy_tofs(retinfo,&tmp,sizeof(*retinfo));
return 0;
}
static int set_serial_info(struct async_struct * info,
struct serial_struct * new_info)
{
struct serial_struct new_serial;
struct async_struct old_info;
unsigned int i,change_irq,change_port;
int retval = 0;
if (!new_info)
return -EFAULT;
memcpy_fromfs(&new_serial,new_info,sizeof(new_serial));
old_info = *info;
change_irq = new_serial.irq != info->irq;
change_port = (new_serial.port != info->port) || (new_serial.hub6 != info->hub6);
if (!suser()) {
if (change_irq || change_port ||
(new_serial.baud_base != info->baud_base) ||
(new_serial.type != info->type) ||
(new_serial.close_delay != info->close_delay) ||
((new_serial.flags & ~ASYNC_USR_MASK) !=
(info->flags & ~ASYNC_USR_MASK)))
return -EPERM;
info->flags = ((info->flags & ~ASYNC_USR_MASK) |
(new_serial.flags & ASYNC_USR_MASK));
info->custom_divisor = new_serial.custom_divisor;
goto check_and_exit;
}
if (new_serial.irq == 2)
new_serial.irq = 9;
if ((new_serial.irq > 15) || (new_serial.port > 0xffff) ||
(new_serial.type < PORT_UNKNOWN) || (new_serial.type > PORT_MAX)) {
return -EINVAL;
}
/* Make sure address is not already in use */
if (new_serial.type) {
for (i = 0 ; i < NR_PORTS; i++)
if ((info != &rs_table[i]) &&
(rs_table[i].port == new_serial.port) &&
rs_table[i].type)
return -EADDRINUSE;
}
if ((change_port || change_irq) && (info->count > 1))
return -EBUSY;
/*
* OK, past this point, all the error checking has been done.
* At this point, we start making changes.....
*/
info->baud_base = new_serial.baud_base;
info->flags = ((info->flags & ~ASYNC_FLAGS) |
(new_serial.flags & ASYNC_FLAGS));
info->custom_divisor = new_serial.custom_divisor;
info->type = new_serial.type;
info->close_delay = new_serial.close_delay * HZ/100;
info->closing_wait = new_serial.closing_wait * HZ/100;
release_region(info->port,8);
if (change_port || change_irq) {
/*
* We need to shutdown the serial port at the old
* port/irq combination.
*/
shutdown(info);
info->irq = new_serial.irq;
info->port = new_serial.port;
info->hub6 = new_serial.hub6;
}
if(info->type != PORT_UNKNOWN)
request_region(info->port,8,"serial(set)");
check_and_exit:
if (!info->port || !info->type)
return 0;
if (info->flags & ASYNC_INITIALIZED) {
if (((old_info.flags & ASYNC_SPD_MASK) !=
(info->flags & ASYNC_SPD_MASK)) ||
(old_info.custom_divisor != info->custom_divisor))
change_speed(info);
} else
retval = startup(info);
return retval;
}
/*
* get_lsr_info - get line status register info
*
* Purpose: Let user call ioctl() to get info when the UART physically
* is emptied. On bus types like RS485, the transmitter must
* release the bus after transmitting. This must be done when
* the transmit shift register is empty, not be done when the
* transmit holding register is empty. This functionality
* allows RS485 driver to be written in user space.
*/
static int get_lsr_info(struct async_struct * info, unsigned int *value)
{
unsigned char status;
unsigned int result;
cli();
status = serial_in(info, UART_LSR);
sti();
result = ((status & UART_LSR_TEMT) ? TIOCSER_TEMT : 0);
put_user(result,value);
return 0;
}
static int get_modem_info(struct async_struct * info, unsigned int *value)
{
unsigned char control, status;
unsigned int result;
control = info->MCR;
cli();
status = serial_in(info, UART_MSR);
sti();
result = ((control & UART_MCR_RTS) ? TIOCM_RTS : 0)
| ((control & UART_MCR_DTR) ? TIOCM_DTR : 0)
| ((status & UART_MSR_DCD) ? TIOCM_CAR : 0)
| ((status & UART_MSR_RI) ? TIOCM_RNG : 0)
| ((status & UART_MSR_DSR) ? TIOCM_DSR : 0)
| ((status & UART_MSR_CTS) ? TIOCM_CTS : 0);
put_user(result,value);
return 0;
}
static int set_modem_info(struct async_struct * info, unsigned int cmd,
unsigned int *value)
{
int error;
unsigned int arg;
error = verify_area(VERIFY_READ, value, sizeof(int));
if (error)
return error;
arg = get_user(value);
switch (cmd) {
case TIOCMBIS:
if (arg & TIOCM_RTS) {
info->MCR |= UART_MCR_RTS;
info->MCR_noint |= UART_MCR_RTS;
}
if (arg & TIOCM_DTR) {
info->MCR |= UART_MCR_DTR;
info->MCR_noint |= UART_MCR_DTR;
}
break;
case TIOCMBIC:
if (arg & TIOCM_RTS) {
info->MCR &= ~UART_MCR_RTS;
info->MCR_noint &= ~UART_MCR_RTS;
}
if (arg & TIOCM_DTR) {
info->MCR &= ~UART_MCR_DTR;
info->MCR_noint &= ~UART_MCR_DTR;
}
break;
case TIOCMSET:
info->MCR = ((info->MCR & ~(UART_MCR_RTS | UART_MCR_DTR))
| ((arg & TIOCM_RTS) ? UART_MCR_RTS : 0)
| ((arg & TIOCM_DTR) ? UART_MCR_DTR : 0));
info->MCR_noint = ((info->MCR_noint
& ~(UART_MCR_RTS | UART_MCR_DTR))
| ((arg & TIOCM_RTS) ? UART_MCR_RTS : 0)
| ((arg & TIOCM_DTR) ? UART_MCR_DTR : 0));
break;
default:
return -EINVAL;
}
cli();
serial_out(info, UART_MCR, info->MCR);
sti();
return 0;
}
static int do_autoconfig(struct async_struct * info)
{
int retval;
if (!suser())
return -EPERM;
if (info->count > 1)
return -EBUSY;
shutdown(info);
cli();
autoconfig(info);
sti();
retval = startup(info);
if (retval)
return retval;
return 0;
}
/*
* This routine sends a break character out the serial port.
*/
static void send_break( struct async_struct * info, int duration)
{
if (!info->port)
return;
current->state = TASK_INTERRUPTIBLE;
current->timeout = jiffies + duration;
cli();
serial_out(info, UART_LCR, serial_inp(info, UART_LCR) | UART_LCR_SBC);
schedule();
serial_out(info, UART_LCR, serial_inp(info, UART_LCR) & ~UART_LCR_SBC);
sti();
}
/*
* This routine returns a bitfield of "wild interrupts". Basically,
* any unclaimed interrupts which is flapping around.
*/
static int check_wild_interrupts(int doprint)
{
int i, mask;
int wild_interrupts = 0;
int irq_lines;
unsigned long timeout;
unsigned long flags;
/* Turn on interrupts (they may be off) */
save_flags(flags); sti();
irq_lines = grab_all_interrupts(0);
/*
* Delay for 0.1 seconds -- we use a busy loop since this may
* occur during the bootup sequence
*/
timeout = jiffies+HZ/10;
while (timeout >= jiffies)
;
rs_triggered = 0; /* Reset after letting things settle */
timeout = jiffies+HZ/10;
while (timeout >= jiffies)
;
for (i = 0, mask = 1; i < 16; i++, mask <<= 1) {
if ((rs_triggered & (1 << i)) &&
(irq_lines & (1 << i))) {
wild_interrupts |= mask;
if (doprint)
printk("Wild interrupt? (IRQ %d)\n", i);
}
}
free_all_interrupts(irq_lines);
restore_flags(flags);
return wild_interrupts;
}
static int get_multiport_struct(struct async_struct * info,
struct serial_multiport_struct *retinfo)
{
struct serial_multiport_struct ret;
struct rs_multiport_struct *multi;
multi = &rs_multiport[info->irq];
ret.port_monitor = multi->port_monitor;
ret.port1 = multi->port1;
ret.mask1 = multi->mask1;
ret.match1 = multi->match1;
ret.port2 = multi->port2;
ret.mask2 = multi->mask2;
ret.match2 = multi->match2;
ret.port3 = multi->port3;
ret.mask3 = multi->mask3;
ret.match3 = multi->match3;
ret.port4 = multi->port4;
ret.mask4 = multi->mask4;
ret.match4 = multi->match4;
ret.irq = info->irq;
memcpy_tofs(retinfo,&ret,sizeof(*retinfo));
return 0;
}
static int set_multiport_struct(struct async_struct * info,
struct serial_multiport_struct *in_multi)
{
struct serial_multiport_struct new_multi;
struct rs_multiport_struct *multi;
int was_multi, now_multi;
int retval;
void (*handler)(int, struct pt_regs *);
if (!suser())
return -EPERM;
if (!in_multi)
return -EFAULT;
memcpy_fromfs(&new_multi, in_multi,
sizeof(struct serial_multiport_struct));
if (new_multi.irq != info->irq || info->irq == 0 ||
!IRQ_ports[info->irq])
return -EINVAL;
multi = &rs_multiport[info->irq];
was_multi = (multi->port1 != 0);
multi->port_monitor = new_multi.port_monitor;
if (multi->port1)
release_region(multi->port1,1);
multi->port1 = new_multi.port1;
multi->mask1 = new_multi.mask1;
multi->match1 = new_multi.match1;
if (multi->port1)
request_region(multi->port1,1,"serial(multiport1)");
if (multi->port2)
release_region(multi->port2,1);
multi->port2 = new_multi.port2;
multi->mask2 = new_multi.mask2;
multi->match2 = new_multi.match2;
if (multi->port2)
request_region(multi->port2,1,"serial(multiport2)");
if (multi->port3)
release_region(multi->port3,1);
multi->port3 = new_multi.port3;
multi->mask3 = new_multi.mask3;
multi->match3 = new_multi.match3;
if (multi->port3)
request_region(multi->port3,1,"serial(multiport3)");
if (multi->port4)
release_region(multi->port4,1);
multi->port4 = new_multi.port4;
multi->mask4 = new_multi.mask4;
multi->match4 = new_multi.match4;
if (multi->port4)
request_region(multi->port4,1,"serial(multiport4)");
now_multi = (multi->port1 != 0);
if (IRQ_ports[info->irq]->next_port &&
(was_multi != now_multi)) {
free_irq(info->irq);
if (now_multi)
handler = rs_interrupt_multi;
else
handler = rs_interrupt;
retval = request_irq(info->irq, handler, SA_INTERRUPT,
"serial");
if (retval) {
printk("Couldn't reallocate serial interrupt "
"driver!!\n");
}
}
return 0;
}
static int rs_ioctl(struct tty_struct *tty, struct file * file,
unsigned int cmd, unsigned long arg)
{
int error;
struct async_struct * info = (struct async_struct *)tty->driver_data;
int retval;
struct async_icount cprev, cnow; /* kernel counter temps */
struct serial_icounter_struct *p_cuser; /* user space */
if (serial_paranoia_check(info, tty->device, "rs_ioctl"))
return -ENODEV;
if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
(cmd != TIOCSERCONFIG) && (cmd != TIOCSERGWILD) &&
(cmd != TIOCSERSWILD) && (cmd != TIOCSERGSTRUCT) &&
(cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
if (tty->flags & (1 << TTY_IO_ERROR))
return -EIO;
}
switch (cmd) {
case TCSBRK: /* SVID version: non-zero arg --> no break */
retval = tty_check_change(tty);
if (retval)
return retval;
tty_wait_until_sent(tty, 0);
if (!arg)
send_break(info, HZ/4); /* 1/4 second */
return 0;
case TCSBRKP: /* support for POSIX tcsendbreak() */
retval = tty_check_change(tty);
if (retval)
return retval;
tty_wait_until_sent(tty, 0);
send_break(info, arg ? arg*(HZ/10) : HZ/4);
return 0;
case TIOCGSOFTCAR:
error = verify_area(VERIFY_WRITE, (void *) arg,sizeof(long));
if (error)
return error;
put_fs_long(C_CLOCAL(tty) ? 1 : 0,
(unsigned long *) arg);
return 0;
case TIOCSSOFTCAR:
arg = get_fs_long((unsigned long *) arg);
tty->termios->c_cflag =
((tty->termios->c_cflag & ~CLOCAL) |
(arg ? CLOCAL : 0));
return 0;
case TIOCMGET:
error = verify_area(VERIFY_WRITE, (void *) arg,
sizeof(unsigned int));
if (error)
return error;
return get_modem_info(info, (unsigned int *) arg);
case TIOCMBIS:
case TIOCMBIC:
case TIOCMSET:
return set_modem_info(info, cmd, (unsigned int *) arg);
case TIOCGSERIAL:
error = verify_area(VERIFY_WRITE, (void *) arg,
sizeof(struct serial_struct));
if (error)
return error;
return get_serial_info(info,
(struct serial_struct *) arg);
case TIOCSSERIAL:
return set_serial_info(info,
(struct serial_struct *) arg);
case TIOCSERCONFIG:
return do_autoconfig(info);
case TIOCSERGWILD:
error = verify_area(VERIFY_WRITE, (void *) arg,
sizeof(int));
if (error)
return error;
put_fs_long(rs_wild_int_mask, (unsigned long *) arg);
return 0;
case TIOCSERGETLSR: /* Get line status register */
error = verify_area(VERIFY_WRITE, (void *) arg,
sizeof(unsigned int));
if (error)
return error;
else
return get_lsr_info(info, (unsigned int *) arg);
case TIOCSERSWILD:
if (!suser())
return -EPERM;
rs_wild_int_mask = get_fs_long((unsigned long *) arg);
if (rs_wild_int_mask < 0)
rs_wild_int_mask = check_wild_interrupts(0);
return 0;
case TIOCSERGSTRUCT:
error = verify_area(VERIFY_WRITE, (void *) arg,
sizeof(struct async_struct));
if (error)
return error;
memcpy_tofs((struct async_struct *) arg,
info, sizeof(struct async_struct));
return 0;
case TIOCSERGETMULTI:
error = verify_area(VERIFY_WRITE, (void *) arg,
sizeof(struct serial_multiport_struct));
if (error)
return error;
return get_multiport_struct(info,
(struct serial_multiport_struct *) arg);
case TIOCSERSETMULTI:
return set_multiport_struct(info,
(struct serial_multiport_struct *) arg);
/*
* Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
* - mask passed in arg for lines of interest
* (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
* Caller should use TIOCGICOUNT to see which one it was
*/
case TIOCMIWAIT:
cli();
cprev = info->icount; /* note the counters on entry */
sti();
while (1) {
interruptible_sleep_on(&info->delta_msr_wait);
/* see if a signal did it */
if (current->signal & ~current->blocked)
return -ERESTARTSYS;
cli();
cnow = info->icount; /* atomic copy */
sti();
if ( ((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
((arg & TIOCM_CD) && (cnow.dcd != cprev.dcd)) ||
((arg & TIOCM_CTS) && (cnow.cts != cprev.cts)) ) {
return 0;
}
cprev = cnow;
}
/* NOTREACHED */
/*
* Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
* Return: write counters to the user passed counter struct
* NB: both 1->0 and 0->1 transitions are counted except for
* RI where only 0->1 is counted.
*/
case TIOCGICOUNT:
error = verify_area(VERIFY_WRITE, (void *) arg,
sizeof(struct serial_icounter_struct));
if (error)
return error;
cli();
cnow = info->icount;
sti();
p_cuser = (struct serial_icounter_struct *) arg;
put_user(cnow.cts, &p_cuser->cts);
put_user(cnow.dsr, &p_cuser->dsr);
put_user(cnow.rng, &p_cuser->rng);
put_user(cnow.dcd, &p_cuser->dcd);
return 0;
default:
return -ENOIOCTLCMD;
}
return 0;
}
static void rs_set_termios(struct tty_struct *tty, struct termios *old_termios)
{
struct async_struct *info = (struct async_struct *)tty->driver_data;
if (tty->termios->c_cflag == old_termios->c_cflag)
return;
change_speed(info);
if ((old_termios->c_cflag & CRTSCTS) &&
!(tty->termios->c_cflag & CRTSCTS)) {
tty->hw_stopped = 0;
rs_start(tty);
}
#if 0
/*
* No need to wake up processes in open wait, since they
* sample the CLOCAL flag once, and don't recheck it.
* XXX It's not clear whether the current behavior is correct
* or not. Hence, this may change.....
*/
if (!(old_termios->c_cflag & CLOCAL) &&
(tty->termios->c_cflag & CLOCAL))
wake_up_interruptible(&info->open_wait);
#endif
}
/*
* ------------------------------------------------------------
* rs_close()
*
* This routine is called when the serial port gets closed. First, we
* wait for the last remaining data to be sent. Then, we unlink its
* async structure from the interrupt chain if necessary, and we free
* that IRQ if nothing is left in the chain.
* ------------------------------------------------------------
*/
static void rs_close(struct tty_struct *tty, struct file * filp)
{
struct async_struct * info = (struct async_struct *)tty->driver_data;
unsigned long flags;
unsigned long timeout;
if (!info || serial_paranoia_check(info, tty->device, "rs_close"))
return;
save_flags(flags); cli();
if (tty_hung_up_p(filp)) {
restore_flags(flags);
return;
}
#ifdef SERIAL_DEBUG_OPEN
printk("rs_close ttys%d, count = %d\n", info->line, info->count);
#endif
if ((tty->count == 1) && (info->count != 1)) {
/*
* Uh, oh. tty->count is 1, which means that the tty
* structure will be freed. Info->count should always
* be one in these conditions. If it's greater than
* one, we've got real problems, since it means the
* serial port won't be shutdown.
*/
printk("rs_close: bad serial port count; tty->count is 1, "
"info->count is %d\n", info->count);
info->count = 1;
}
if (--info->count < 0) {
printk("rs_close: bad serial port count for ttys%d: %d\n",
info->line, info->count);
info->count = 0;
}
if (info->count) {
restore_flags(flags);
return;
}
info->flags |= ASYNC_CLOSING;
/*
* Save the termios structure, since this port may have
* separate termios for callout and dialin.
*/
if (info->flags & ASYNC_NORMAL_ACTIVE)
info->normal_termios = *tty->termios;
if (info->flags & ASYNC_CALLOUT_ACTIVE)
info->callout_termios = *tty->termios;
/*
* Now we wait for the transmit buffer to clear; and we notify
* the line discipline to only process XON/XOFF characters.
*/
tty->closing = 1;
if (info->closing_wait != ASYNC_CLOSING_WAIT_NONE)
tty_wait_until_sent(tty, info->closing_wait);
/*
* At this point we stop accepting input. To do this, we
* disable the receive line status interrupts, and tell the
* interrupt driver to stop checking the data ready bit in the
* line status register.
*/
info->IER &= ~UART_IER_RLSI;
info->read_status_mask &= ~UART_LSR_DR;
if (info->flags & ASYNC_INITIALIZED) {
serial_out(info, UART_IER, info->IER);
/*
* Before we drop DTR, make sure the UART transmitter
* has completely drained; this is especially
* important if there is a transmit FIFO!
*/
timeout = jiffies+HZ;
while (!(serial_inp(info, UART_LSR) & UART_LSR_TEMT)) {
current->state = TASK_INTERRUPTIBLE;
current->timeout = jiffies + info->timeout;
schedule();
if (jiffies > timeout)
break;
}
}
shutdown(info);
if (tty->driver.flush_buffer)
tty->driver.flush_buffer(tty);
if (tty->ldisc.flush_buffer)
tty->ldisc.flush_buffer(tty);
tty->closing = 0;
info->event = 0;
info->tty = 0;
if (tty->ldisc.num != ldiscs[N_TTY].num) {
if (tty->ldisc.close)
(tty->ldisc.close)(tty);
tty->ldisc = ldiscs[N_TTY];
tty->termios->c_line = N_TTY;
if (tty->ldisc.open)
(tty->ldisc.open)(tty);
}
if (info->blocked_open) {
if (info->close_delay) {
current->state = TASK_INTERRUPTIBLE;
current->timeout = jiffies + info->close_delay;
schedule();
}
wake_up_interruptible(&info->open_wait);
}
info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE|
ASYNC_CLOSING);
wake_up_interruptible(&info->close_wait);
restore_flags(flags);
}
/*
* rs_hangup() --- called by tty_hangup() when a hangup is signaled.
*/
void rs_hangup(struct tty_struct *tty)
{
struct async_struct * info = (struct async_struct *)tty->driver_data;
if (serial_paranoia_check(info, tty->device, "rs_hangup"))
return;
rs_flush_buffer(tty);
shutdown(info);
info->event = 0;
info->count = 0;
info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE);
info->tty = 0;
wake_up_interruptible(&info->open_wait);
}
/*
* ------------------------------------------------------------
* rs_open() and friends
* ------------------------------------------------------------
*/
static int block_til_ready(struct tty_struct *tty, struct file * filp,
struct async_struct *info)
{
struct wait_queue wait = { current, NULL };
int retval;
int do_clocal = 0;
/*
* If the device is in the middle of being closed, then block
* until it's done, and then try again.
*/
if (tty_hung_up_p(filp) ||
(info->flags & ASYNC_CLOSING)) {
interruptible_sleep_on(&info->close_wait);
#ifdef SERIAL_DO_RESTART
if (info->flags & ASYNC_HUP_NOTIFY)
return -EAGAIN;
else
return -ERESTARTSYS;
#else
return -EAGAIN;
#endif
}
/*
* If this is a callout device, then just make sure the normal
* device isn't being used.
*/
if (tty->driver.subtype == SERIAL_TYPE_CALLOUT) {
if (info->flags & ASYNC_NORMAL_ACTIVE)
return -EBUSY;
if ((info->flags & ASYNC_CALLOUT_ACTIVE) &&
(info->flags & ASYNC_SESSION_LOCKOUT) &&
(info->session != current->session))
return -EBUSY;
if ((info->flags & ASYNC_CALLOUT_ACTIVE) &&
(info->flags & ASYNC_PGRP_LOCKOUT) &&
(info->pgrp != current->pgrp))
return -EBUSY;
info->flags |= ASYNC_CALLOUT_ACTIVE;
return 0;
}
/*
* If non-blocking mode is set, or the port is not enabled,
* then make the check up front and then exit.
*/
if ((filp->f_flags & O_NONBLOCK) ||
(tty->flags & (1 << TTY_IO_ERROR))) {
if (info->flags & ASYNC_CALLOUT_ACTIVE)
return -EBUSY;
info->flags |= ASYNC_NORMAL_ACTIVE;
return 0;
}
if (info->flags & ASYNC_CALLOUT_ACTIVE) {
if (info->normal_termios.c_cflag & CLOCAL)
do_clocal = 1;
} else {
if (tty->termios->c_cflag & CLOCAL)
do_clocal = 1;
}
/*
* Block waiting for the carrier detect and the line to become
* free (i.e., not in use by the callout). While we are in
* this loop, info->count is dropped by one, so that
* rs_close() knows when to free things. We restore it upon
* exit, either normal or abnormal.
*/
retval = 0;
add_wait_queue(&info->open_wait, &wait);
#ifdef SERIAL_DEBUG_OPEN
printk("block_til_ready before block: ttys%d, count = %d\n",
info->line, info->count);
#endif
cli();
if (!tty_hung_up_p(filp))
info->count--;
sti();
info->blocked_open++;
while (1) {
cli();
if (!(info->flags & ASYNC_CALLOUT_ACTIVE))
serial_out(info, UART_MCR,
serial_inp(info, UART_MCR) |
(UART_MCR_DTR | UART_MCR_RTS));
sti();
current->state = TASK_INTERRUPTIBLE;
if (tty_hung_up_p(filp) ||
!(info->flags & ASYNC_INITIALIZED)) {
#ifdef SERIAL_DO_RESTART
if (info->flags & ASYNC_HUP_NOTIFY)
retval = -EAGAIN;
else
retval = -ERESTARTSYS;
#else
retval = -EAGAIN;
#endif
break;
}
if (!(info->flags & ASYNC_CALLOUT_ACTIVE) &&
!(info->flags & ASYNC_CLOSING) &&
(do_clocal || (serial_in(info, UART_MSR) &
UART_MSR_DCD)))
break;
if (current->signal & ~current->blocked) {
retval = -ERESTARTSYS;
break;
}
#ifdef SERIAL_DEBUG_OPEN
printk("block_til_ready blocking: ttys%d, count = %d\n",
info->line, info->count);
#endif
schedule();
}
current->state = TASK_RUNNING;
remove_wait_queue(&info->open_wait, &wait);
if (!tty_hung_up_p(filp))
info->count++;
info->blocked_open--;
#ifdef SERIAL_DEBUG_OPEN
printk("block_til_ready after blocking: ttys%d, count = %d\n",
info->line, info->count);
#endif
if (retval)
return retval;
info->flags |= ASYNC_NORMAL_ACTIVE;
return 0;
}
/*
* This routine is called whenever a serial port is opened. It
* enables interrupts for a serial port, linking in its async structure into
* the IRQ chain. It also performs the serial-specific
* initialization for the tty structure.
*/
int rs_open(struct tty_struct *tty, struct file * filp)
{
struct async_struct *info;
int retval, line;
unsigned long page;
line = MINOR(tty->device) - tty->driver.minor_start;
if ((line < 0) || (line >= NR_PORTS))
return -ENODEV;
info = rs_table + line;
if (serial_paranoia_check(info, tty->device, "rs_open"))
return -ENODEV;
#ifdef SERIAL_DEBUG_OPEN
printk("rs_open %s%d, count = %d\n", tty->driver.name, info->line,
info->count);
#endif
info->count++;
tty->driver_data = info;
info->tty = tty;
if (!tmp_buf) {
page = get_free_page(GFP_KERNEL);
if (!page)
return -ENOMEM;
if (tmp_buf)
free_page(page);
else
tmp_buf = (unsigned char *) page;
}
/*
* Start up serial port
*/
retval = startup(info);
if (retval)
return retval;
retval = block_til_ready(tty, filp, info);
if (retval) {
#ifdef SERIAL_DEBUG_OPEN
printk("rs_open returning after block_til_ready with %d\n",
retval);
#endif
return retval;
}
if ((info->count == 1) && (info->flags & ASYNC_SPLIT_TERMIOS)) {
if (tty->driver.subtype == SERIAL_TYPE_NORMAL)
*tty->termios = info->normal_termios;
else
*tty->termios = info->callout_termios;
change_speed(info);
}
info->session = current->session;
info->pgrp = current->pgrp;
#ifdef SERIAL_DEBUG_OPEN
printk("rs_open ttys%d successful...", info->line);
#endif
return 0;
}
/*
* ---------------------------------------------------------------------
* rs_init() and friends
*
* rs_init() is called at boot-time to initialize the serial driver.
* ---------------------------------------------------------------------
*/
/*
* This routine prints out the appropriate serial driver version
* number, and identifies which options were configured into this
* driver.
*/
static void show_serial_version(void)
{
printk("Serial driver version 4.11 with");
#ifdef CONFIG_HUB6
printk(" HUB-6");
#define SERIAL_OPT
#endif
#ifdef SERIAL_OPT
printk(" enabled\n");
#else
printk(" no serial options enabled\n");
#endif
#undef SERIAL_OPT
}
/*
* This routine is called by do_auto_irq(); it attempts to determine
* which interrupt a serial port is configured to use. It is not
* fool-proof, but it works a large part of the time.
*/
static int get_auto_irq(struct async_struct *info)
{
unsigned char save_MCR, save_IER, save_ICP=0;
unsigned short ICP=0, port = info->port;
unsigned long timeout;
/*
* Enable interrupts and see who answers
*/
rs_irq_triggered = 0;
cli();
save_IER = serial_inp(info, UART_IER);
save_MCR = serial_inp(info, UART_MCR);
if (info->flags & ASYNC_FOURPORT) {
serial_outp(info, UART_MCR, UART_MCR_DTR | UART_MCR_RTS);
serial_outp(info, UART_IER, 0x0f); /* enable all intrs */
ICP = (port & 0xFE0) | 0x01F;
save_ICP = inb_p(ICP);
outb_p(0x80, ICP);
(void) inb_p(ICP);
} else {
serial_outp(info, UART_MCR,
UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2);
serial_outp(info, UART_IER, 0x0f); /* enable all intrs */
}
sti();
/*
* Next, clear the interrupt registers.
*/
(void)serial_inp(info, UART_LSR);
(void)serial_inp(info, UART_RX);
(void)serial_inp(info, UART_IIR);
(void)serial_inp(info, UART_MSR);
timeout = jiffies+2*HZ/100;
while (timeout >= jiffies) {
if (rs_irq_triggered)
break;
}
/*
* Now check to see if we got any business, and clean up.
*/
cli();
serial_outp(info, UART_IER, save_IER);
serial_outp(info, UART_MCR, save_MCR);
if (info->flags & ASYNC_FOURPORT)
outb_p(save_ICP, ICP);
sti();
return(rs_irq_triggered);
}
/*
* Calls get_auto_irq() multiple times, to make sure we don't get
* faked out by random interrupts
*/
static int do_auto_irq(struct async_struct * info)
{
unsigned port = info->port;
int irq_lines = 0;
int irq_try_1 = 0, irq_try_2 = 0;
int retries;
unsigned long flags;
if (!port)
return 0;
/* Turn on interrupts (they may be off) */
save_flags(flags); sti();
irq_lines = grab_all_interrupts(rs_wild_int_mask);
for (retries = 0; retries < 5; retries++) {
if (!irq_try_1)
irq_try_1 = get_auto_irq(info);
if (!irq_try_2)
irq_try_2 = get_auto_irq(info);
if (irq_try_1 && irq_try_2) {
if (irq_try_1 == irq_try_2)
break;
irq_try_1 = irq_try_2 = 0;
}
}
restore_flags(flags);
free_all_interrupts(irq_lines);
return (irq_try_1 == irq_try_2) ? irq_try_1 : 0;
}
/*
* This routine is called by rs_init() to initialize a specific serial
* port. It determines what type of UART chip this serial port is
* using: 8250, 16450, 16550, 16550A. The important question is
* whether or not this UART is a 16550A or not, since this will
* determine whether or not we can use its FIFO features or not.
*/
static void autoconfig(struct async_struct * info)
{
unsigned char status1, status2, scratch, scratch2;
unsigned port = info->port;
unsigned long flags;
info->type = PORT_UNKNOWN;
if (!port)
return;
save_flags(flags); cli();
/*
* Do a simple existence test first; if we fail this, there's
* no point trying anything else.
*
* 0x80 is used as a nonsense port to prevent against false
* positives due to ISA bus float. The assumption is that
* 0x80 is a non-existent port; which should be safe since
* include/asm/io.h also makes this assumption.
*/
scratch = serial_inp(info, UART_IER);
serial_outp(info, UART_IER, 0);
outb(0xff, 0x080);
scratch2 = serial_inp(info, UART_IER);
serial_outp(info, UART_IER, scratch);
if (scratch2) {
restore_flags(flags);
return; /* We failed; there's nothing here */
}
/*
* Check to see if a UART is really there. Certain broken
* internal modems based on the Rockwell chipset fail this
* test, because they apparently don't implement the loopback
* test mode. So this test is skipped on the COM 1 through
* COM 4 ports. This *should* be safe, since no board
* manufacturer would be stupid enough to design a board
* that conflicts with COM 1-4 --- we hope!
*/
if (!(info->flags & ASYNC_SKIP_TEST)) {
scratch = serial_inp(info, UART_MCR);
serial_outp(info, UART_MCR, UART_MCR_LOOP | scratch);
scratch2 = serial_inp(info, UART_MSR);
serial_outp(info, UART_MCR, UART_MCR_LOOP | 0x0A);
status1 = serial_inp(info, UART_MSR) & 0xF0;
serial_outp(info, UART_MCR, scratch);
serial_outp(info, UART_MSR, scratch2);
if (status1 != 0x90) {
restore_flags(flags);
return;
}
}
/*
* If the AUTO_IRQ flag is set, try to do the automatic IRQ
* detection.
*/
if (info->flags & ASYNC_AUTO_IRQ)
info->irq = do_auto_irq(info);
scratch2 = serial_in(info, UART_LCR);
serial_outp(info, UART_LCR, scratch2 | UART_LCR_DLAB);
serial_outp(info, UART_EFR, 0); /* EFR is the same as FCR */
serial_outp(info, UART_LCR, scratch2);
serial_outp(info, UART_FCR, UART_FCR_ENABLE_FIFO);
scratch = serial_in(info, UART_IIR) >> 6;
info->xmit_fifo_size = 1;
switch (scratch) {
case 0:
info->type = PORT_16450;
break;
case 1:
info->type = PORT_UNKNOWN;
break;
case 2:
info->type = PORT_16550;
break;
case 3:
serial_outp(info, UART_LCR, scratch2 | UART_LCR_DLAB);
if (serial_in(info, UART_EFR) == 0) {
info->type = PORT_16650;
info->xmit_fifo_size = 32;
} else {
info->type = PORT_16550A;
info->xmit_fifo_size = 16;
}
serial_outp(info, UART_LCR, scratch2);
break;
}
if (info->type == PORT_16450) {
scratch = serial_in(info, UART_SCR);
serial_outp(info, UART_SCR, 0xa5);
status1 = serial_in(info, UART_SCR);
serial_outp(info, UART_SCR, 0x5a);
status2 = serial_in(info, UART_SCR);
serial_outp(info, UART_SCR, scratch);
if ((status1 != 0xa5) || (status2 != 0x5a))
info->type = PORT_8250;
}
request_region(info->port,8,"serial(auto)");
/*
* Reset the UART.
*/
#if defined(__alpha__) && !defined(CONFIG_PCI)
/*
* I wonder what DEC did to the OUT1 and OUT2 lines?
* clearing them results in endless interrupts.
*/
serial_outp(info, UART_MCR, 0x0c);
#else
serial_outp(info, UART_MCR, 0x00);
#endif
serial_outp(info, UART_FCR, (UART_FCR_CLEAR_RCVR |
UART_FCR_CLEAR_XMIT));
(void)serial_in(info, UART_RX);
restore_flags(flags);
}
/*
* The serial driver boot-time initialization code!
*/
int rs_init(void)
{
int i;
struct async_struct * info;
bh_base[SERIAL_BH].routine = do_serial_bh;
enable_bh(SERIAL_BH);
timer_table[RS_TIMER].fn = rs_timer;
timer_table[RS_TIMER].expires = 0;
#ifdef CONFIG_AUTO_IRQ
rs_wild_int_mask = check_wild_interrupts(1);
#endif
for (i = 0; i < 16; i++) {
IRQ_ports[i] = 0;
IRQ_timeout[i] = 0;
memset(&rs_multiport[i], 0, sizeof(struct rs_multiport_struct));
}
show_serial_version();
/* Initialize the tty_driver structure */
memset(&serial_driver, 0, sizeof(struct tty_driver));
serial_driver.magic = TTY_DRIVER_MAGIC;
serial_driver.name = "ttyS";
serial_driver.major = TTY_MAJOR;
serial_driver.minor_start = 64;
serial_driver.num = NR_PORTS;
serial_driver.type = TTY_DRIVER_TYPE_SERIAL;
serial_driver.subtype = SERIAL_TYPE_NORMAL;
serial_driver.init_termios = tty_std_termios;
serial_driver.init_termios.c_cflag =
B9600 | CS8 | CREAD | HUPCL | CLOCAL;
serial_driver.flags = TTY_DRIVER_REAL_RAW;
serial_driver.refcount = &serial_refcount;
serial_driver.table = serial_table;
serial_driver.termios = serial_termios;
serial_driver.termios_locked = serial_termios_locked;
serial_driver.open = rs_open;
serial_driver.close = rs_close;
serial_driver.write = rs_write;
serial_driver.put_char = rs_put_char;
serial_driver.flush_chars = rs_flush_chars;
serial_driver.write_room = rs_write_room;
serial_driver.chars_in_buffer = rs_chars_in_buffer;
serial_driver.flush_buffer = rs_flush_buffer;
serial_driver.ioctl = rs_ioctl;
serial_driver.throttle = rs_throttle;
serial_driver.unthrottle = rs_unthrottle;
serial_driver.set_termios = rs_set_termios;
serial_driver.stop = rs_stop;
serial_driver.start = rs_start;
serial_driver.hangup = rs_hangup;
/*
* The callout device is just like normal device except for
* major number and the subtype code.
*/
callout_driver = serial_driver;
callout_driver.name = "cua";
callout_driver.major = TTYAUX_MAJOR;
callout_driver.subtype = SERIAL_TYPE_CALLOUT;
if (tty_register_driver(&serial_driver))
panic("Couldn't register serial driver\n");
if (tty_register_driver(&callout_driver))
panic("Couldn't register callout driver\n");
for (i = 0, info = rs_table; i < NR_PORTS; i++,info++) {
info->magic = SERIAL_MAGIC;
info->line = i;
info->tty = 0;
info->type = PORT_UNKNOWN;
info->custom_divisor = 0;
info->close_delay = 5*HZ/10;
info->closing_wait = 30*HZ;
info->x_char = 0;
info->event = 0;
info->count = 0;
info->blocked_open = 0;
info->tqueue.routine = do_softint;
info->tqueue.data = info;
info->tqueue_hangup.routine = do_serial_hangup;
info->tqueue_hangup.data = info;
info->callout_termios =callout_driver.init_termios;
info->normal_termios = serial_driver.init_termios;
info->open_wait = 0;
info->close_wait = 0;
info->delta_msr_wait = 0;
info->icount.cts = info->icount.dsr =
info->icount.rng = info->icount.dcd = 0;
info->next_port = 0;
info->prev_port = 0;
if (info->irq == 2)
info->irq = 9;
if (!(info->flags & ASYNC_BOOT_AUTOCONF))
continue;
autoconfig(info);
if (info->type == PORT_UNKNOWN)
continue;
printk("tty%02d%s at 0x%04x (irq = %d)", info->line,
(info->flags & ASYNC_FOURPORT) ? " FourPort" : "",
info->port, info->irq);
switch (info->type) {
case PORT_8250:
printk(" is a 8250\n");
break;
case PORT_16450:
printk(" is a 16450\n");
break;
case PORT_16550:
printk(" is a 16550\n");
break;
case PORT_16550A:
printk(" is a 16550A\n");
break;
case PORT_16650:
printk(" is a 16650\n");
break;
default:
printk("\n");
break;
}
}
return 0;
}
/*
* register_serial and unregister_serial allows for serial ports to be
* configured at run-time, to support PCMCIA modems.
*/
int register_serial(struct serial_struct *req)
{
int i;
unsigned long flags;
struct async_struct *info;
save_flags(flags);
cli();
for (i = 0; i < NR_PORTS; i++) {
if (rs_table[i].port == req->port)
break;
}
if (i == NR_PORTS) {
for (i = 0; i < NR_PORTS; i++)
if ((rs_table[i].type == PORT_UNKNOWN) &&
(rs_table[i].count == 0))
break;
}
if (i == NR_PORTS) {
restore_flags(flags);
return -1;
}
info = &rs_table[i];
if (rs_table[i].count) {
restore_flags(flags);
printk("Couldn't configure serial #%d (port=%d,irq=%d): "
"device already open\n", i, req->port, req->irq);
return -1;
}
info->irq = req->irq;
info->port = req->port;
autoconfig(info);
if (info->type == PORT_UNKNOWN) {
restore_flags(flags);
printk("register_serial(): autoconfig failed\n");
return -1;
}
printk("tty%02d at 0x%04x (irq = %d)", info->line,
info->port, info->irq);
switch (info->type) {
case PORT_8250:
printk(" is a 8250\n"); break;
case PORT_16450:
printk(" is a 16450\n"); break;
case PORT_16550:
printk(" is a 16550\n"); break;
case PORT_16550A:
printk(" is a 16550A\n"); break;
default:
printk("\n"); break;
}
restore_flags(flags);
return info->line;
}
void unregister_serial(int line)
{
unsigned long flags;
struct async_struct *info = &rs_table[line];
save_flags(flags);
cli();
if (info->tty)
tty_hangup(info->tty);
info->type = PORT_UNKNOWN;
printk("tty%02d unloaded\n", info->line);
restore_flags(flags);
}